Selective Heat Insulation of Combustion Chamber Walls for a DI Diesel Engine with Monolithic Ceramics

The engine performance and emissions characteristics of a single-cylinder DI diesel engine were experimentally investigated. The combustion chamber walls of the engine were thermally insulated with ceramic materials of SSN (Sintered Silicon Nitride) and PSZ (Partially Stabilized Zirconia). Fuel economy and emissions characteristics were improved by insulating selected locations of the combustion chamber walls. The selective insulation helped to create activated diffusion combustion and resulted in more efficient use of the intake air.